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Activated carbons (AC) play a key role in enabling the reaction kinetic of cathodes in lithium ion batteries (LIBs). However, the charge transfer dynamics and reaction kinetics mechanism of AC composited cathodes along their thickness direction are still poorly understood. Herein, we systematically compare the internal reactive process evolutions of AC modified LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cathodes and pristine NCM622 cathodes at high C-rates. The charge transfer dynamic is revealed by the time of flight secondary ion mass spectrometry and X-ray photoelectron spectra analyzes. The addition of AC endows the NCM622 cathode regions close to the current collector possess higher lithium ion concentrations, meanwhile more Ni2+ can be converted into Ni3+. The results of COMSOL Multiphysics simulations based on the porous electrode theory is analyzed to explore reaction kinetics mechanism. AC in NCM622 cathodes homogenizes the reaction distributions, contributing to the boosted reaction kinetic, eventually, resulting in the high utilization of active materials. These findings provide a direct way to reduce solid-state diffusion resistances and accelerate reaction kinetics of electrodes, which is critical for developing batteries with long cycle stability and rate performance at high rates. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal and sol-gel method were combined to prepare carbon microspheres. • Carbon microspheres with multi-layer dendritic hollow structure, high specific surface area and abundant micropores were successfully prepared. • Excellent cycle stability and great specific capacitance were obtained by the supercapacitor prepared from the carbon microspheres. The electrochemical properties of corn starch (CS)-based hydrothermal carbon microsphere (CMS) electrode materials for supercapacitor are closely related to their structures. Herein, cetyltrimethyl ammonium bromide (CTAB) was used as a soft template to form the corn starch (CS)-based carbon microspheres with radial hollow structure in the inner and middle layers by hydrothermal and sol-gel method. Due to the introduction of multi-layer hollow structure of carbon microsphere, more micropores were produced during CO 2 activation, which increased the specific surface area and improved the capacitance performance. Compared to commercial activated carbon, the four different morphologies of corn starch CMS had better electrochemical performances. Consequently, the proposed CO 2 –(CTAB)-CS-CS exhibits a high discharge specific capacitance of 242.5F/g at 1 A/g in three-electrode system with 6 M KOH electrolyte, better than commercial activated carbon with 208.5F/g. Moreover, excellent stability is achieved for CO 2 –(CTAB)-CS-CS with approximately 97.14 % retention of the initial specific capacitance value after 10,000 cycles at a current density of 2 A/g, while the commercial activated carbon has 86.96 % retention. This implies that the corn starch-based multilayer hollow CMS could be a promising electrode material for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Laser Doppler velocimetry (LDV) is a high precision instrument based on the Doppler effect of a laser, and it would greatly improve the performance of vehicle navigation and vehicle velocity metrology for its advantages. To reduce the measurement error produced by a jolt of a vehicle, a novel Janus-configured all fibre LDV is designed. The system comprising two independent interferometers is connected by 1.55 μm single mode fibre devices. Road experiments are carried out to compare the performances of the microwave radar, single beam LDV and Janus-configured LDV. The Janus-configured LDV is reliable to measure the velocity of the vehicle and its root-mean-square error is 0.0222 m/s, while it is 0.0284 m/s for the single beam LDV. The results validate that the designed LDV can achieve improved performance of vehicle velocity measurement. [ABSTRACT FROM AUTHOR]

Beam pointing angle (BPA) is one of the key parameters that affects the operation performance of the laser Doppler velocimetry (LDV) system. By considering velocity sensitivity and echo power, for the first time, the optimized BPA of vehicle LDV is analyzed. Assuming mounting error is within ±1.0 deg, the reflectivity and roughness are variable for different scenarios, the optimized BPA is obtained in the range from 29 to 43 deg. Therefore, velocity sensitivity is in the range of 1.25 to 1.76 MHz(m/s), and the percentage of normalized echo power at optimized BPA with respect to that at 0 deg is greater than 53.49%. Laboratory experiments with a rotating table are done with different BPAs of 10, 35, and 66 deg, and the results coincide with the theoretical analysis. Further, vehicle experiment with optimized BPA of 35 deg is conducted by comparison with microwave radar (accuracy of ±0.5% full scale output). The root-mean-square error of LDV's results is smaller than the Microstar II's, 0.0202 and 0.1495 m/s, corresponding to LDV and Microstar II, respectively, and the mean velocity discrepancy is 0.032 m/s. It is also proven that with the optimized BPA both high velocity sensitivity and acceptable echo power can simultaneously be guaranteed. [ABSTRACT FROM AUTHOR]

A novel type of cellular-uptake-shielding multifunctional envelope-type mesoporous silica nanoparticle (MEMSN) was designed for tumor-triggered targeting drug delivery to cancerous cells. β-Cyclodextrin (β-CD) was anchored on the surface of mesoporous silica nanoparticles via disulfide linking for glutathione-induced intracellular drug release. Then a peptide sequence containing Arg-Gly-Asp (RGD) motif and matrix metalloproteinase (MMP) substrate peptide Pro-Leu-Gly-Val-Arg (PLGVR) was introduced onto the surface of the nanoparticles via host–guest interaction. To protect the targeting ligand and prevent the nanoparticles from being uptaken by normal cells, the nanoparticles were further decorated with poly(aspartic acid) (PASP) to obtain MEMSN. In vitro study demonstrated that MEMSN was shielded against normal cells. After reaching the tumor cells, the targeting property could be switched on by removing the PASP protection layer via hydrolyzation of PLGVR at the MMP-rich tumor cells, which enabled the easy uptake of drug-loaded nanoparticles by tumor cells and subsequent glutathione-induced drug release intracellularly. [ABSTRACT FROM AUTHOR]

Abstract  We present a simulation and visualization system for a critical application—analysis of the thermal fluid dynamics inside a pressurized water reactor of a nuclear power plant when cold water is injected into the reactor vessel. We employ a hybrid thermal lattice Boltzmann method (HTLBM), which has the advantages of ease of parallelization and ease of handling complex simulation boundaries. For efficient computation and storage of the irregular-shaped simulation domain, we classify the domain into nonempty and empty cells and apply a novel packing technique to organize the nonempty cells. This method is implemented on a GPU cluster for acceleration. We demonstrate the formation of cold-water plumes in the reactor vessel. A set of interactive visualization tools, such as side-view slices, 3D volume rendering, thermal layers rendering, and panorama rendering, are provided to collectively visualize the structure and dynamics of the temperature field in the vessel. To the best of our knowledge, this is the first system that combines 3D simulation and visualization for analyzing thermal shock risk in a pressurized water reactor. [ABSTRACT FROM AUTHOR]

Due to its high performance/cost ratio, a GPU cluster is an attractive platform for large scale general-purpose computation and visualization applications. However, the programming model for high performance general-purpose computation on GPU clusters remains a complex problem. In this paper, we introduce the Zippy frame-work, a general and scalable solution to this problem. It abstracts the GPU cluster programming with a two-level parallelism hierarchy and a non-uniform memory access (NUMA) model. Zippy preserves the advantages of both message passing and shared-memory models. It employs global arrays (GA) to simplify the communication, synchronization, and collaboration among multiple GPUs. Moreover, it exposes data locality to the programmer for optimal performance and scalability. We present three example applications developed with Zippy: sort-last volume rendering, Marching Cubes isosurface extraction and rendering, and lattice Boltzmann flow simulation with online visualization. They demonstrate that Zippy can ease the development and integration of parallel visualization, graphics, and computation modules on a GPU cluster. [ABSTRACT FROM AUTHOR]

SiC whiskers are bridged on rGO through SiC nuclei (C-Si covalent bonds). C-O groups in graphene promote the reaction possibility of SiC nucleation. Special defective configurations induce unpaired electrons of the surrounding carbon atoms, which is the prerequisite of the C-Si covalent bonds. With the construction of C-Si bonds, SiCw@rGO composites achieve good thermal conductivity and electrical insulation capability. [Display omitted] • SiCw@rGO thermal conductive filler was synthesized, in which SiCw are bridged on rGO through SiC nuclei (C-Si covalent bonds). • C-O groups in graphene promote the reaction possibility of SiC nucleation. • Special defective graphene configurations induce the unpaired electrons, enhancing the formation of C-Si covalent bonds. • With the construction of C-Si covalent bonds, SiCw@rGO/EP achieves good thermal conductivity property. SiC whisker (SiCw) anchoring on reduced graphene oxide (rGO) is a promising thermal conductive filler, which not only constructs the high-effective phonon transmission pathway but also resolves the agglomeration phenomenon of rGO. However, how to quantificationally anchor SiCw on rGO to build a phonon transmission pathway is incompletely understood. That is, the nucleation mechanism of SiCw requires a full investigation. Here, SiCw@rGO was synthesized by stacking bed method using rGO and rice husk ash as materials, in which SiCw is bridged on the rGO sheets through SiC crystal nucleus (C-Si covalent bonds). The experimental and density functional theoretical results reveal that the oxygen-containing defects (C-O groups) of rGO provide favorable sites for SiC nucleation and promote the yield of SiCw. Additionally, some specific defects of rGO induce the unpaired electrons of the surrounding carbon atoms, which is the prerequisite of the formation of C-Si covalent bonds. The construction of C-Si bonds between SiCw and rGO serves to enhance phonon accessibility, making SiCw@rGO composites achieve good thermal conductivity property and electrical insulation performance. The combination of experimental and theoretical research provides guides for the design of high-efficient thermal conductive materials. [ABSTRACT FROM AUTHOR]

Suggests two convection indices to measure the variability of the Indian summer monsoon (ISM) and the Southeast Asian summer monsoon. Difficulty in using a single monsoon index to characterize the interannual variability of a regional monsoon; Action centers of the south Asian summer monsoon; Relationships between the convection and circulation variabilities.

Kiruna-type iron oxide-apatite (IOA) deposits, an important source of iron, show close associations with andesitic subvolcanic intrusions. However, the processes of ore formation and the mechanism controlling iron concentration remain uncertain. Here, we report the widespread presence of high-temperature (>800°C) water-poor multisolid hydrosaline liquid inclusions in pre-and syn-ore minerals from IOA deposits of eastern China. These inclusions consistently homogenize to a liquid phase by vapor disappearance and mostly contain 3 to 10 wt % Fe, signifying a substantial capacity for iron transportation by such hydrosaline liquids. We propose that the hydrosaline liquids were likely immiscible from the dioritic magmas with high Cl/H2O in subvolcanic settings. Subsequent reaction with host rocks and/or decompression and cooling of the hydrosaline liquids is deemed responsible for the simultaneous formation of high-temperature alteration and magnetite ores, thereby providing important insights into the distinctive characteristics of IOA deposits in shallow magmatic-hydrothermal systems. [ABSTRACT FROM AUTHOR]

The SiC whiskers/hollow carbon microspheres (SiCw/HCMS) were successfully synthesized by a combination of the spray drying technology and the carbothermal reduction method. The anchoring of SiCw on HCMS shells improves the thermostability of composites and induces the formation of new heterointerfaces between SiC whiskers and HCMS. Experimental characterizations together with DFT calculations show that compared to intrinsic defects and functional groups in SiCw/HCMS, the formed heterointerfaces trigger the separation of positive and negative charges and induce large dipole moments, resulting in the intensive dielectric polarization loss. Consequently, SiCw/HCMS samples achieve an excellent electromagnetic wave absorption, where the reflection loss value of SiCw/HCMS-1450 reaches to −48.60 dB at 8.0 GHz with a thickness of 2.6 mm and the maximum effective absorbing bandwidth is 4.34 GHz. This work investigates a deep insight into the relationship between interfacial polarization loss and the electromagnetic wave attenuation and designs a novel absorbent that exhibits great potential for electromagnetic wave absorption at high-temperature environments. SiC whiskers/hollow carbon microspheres (SiCw/HCMS) were successfully designed and synthesized by spray drying technology and carbothermal reduction method. Benefiting for designed structure, the heterointerfaces between SiC whiskers and HCMS induce the separation of positive and negative charges and result in large dipole moment, contributing to a significant polarization loss. SiCw/HCMS samples exhibit a superior electromagnetic wave absorption performance. Image 1 • SiCw/HCMS were synthesized by a combination of the spray drying technology and the carbothermal reduction method. • The heterointerfaces induce a large polarization loss than that of defective structures in SiCw/HCMS samples. • RL value of SiCw/HCMS-1450 reaches −48.60 dB at 8.0 GHz with a thickness of 2.6 mm and the EAB is 4.34 GHz. [ABSTRACT FROM AUTHOR]

The phase relation of harmonics in high-intensity focused ultrasound is investigated numerically and experimentally. The nonlinear Westervelt equation is solved to model nonlinear focused sound field by using the finite difference time domain method. Experimental waveforms are measured by a robust needle hydrophone. Then the relative phase quantity is introduced and obtained by using the zero-phase filter. The results show that the nth harmonic relative phase quantity is approximately (n — 1)π/3 at geometric center and increases along the axial direction. Moreover, the relative phase quantity decreases with the increase of source amplitude. This phase relation gives an explanation of some nonlinear phenomena such as the discrepancy of positive and negative pressure. [ABSTRACT FROM AUTHOR]

Seismic damage detection of concrete dams has always attracted much attention in hydraulic structure community. In this article, a novel seismic damage detection system was developed to perform seismic damage monitoring in concrete dams. As its importance in achieving the dam damage detection, the arrangement of a distributed lead zirconate titanate sensor network was introduced in detail. A dam model system with a distributed lead zirconate titanate sensor network was used as an object for verification. A shaking table was used to simulate the earthquake ground motion for the object to be tested. The seismic damage detection system could be used in not only the seismic damage process monitoring by measuring the dynamic stress history but also the distributed detecting of the dam damaged region. By analyzing the sensor signals, the emergence and development of the structural damages could be monitored timely. A damage index matrix was presented to evaluate the damage status of the dam in different paths. The experimental results verified the timeliness and the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Introduction: Previous studies have explored prediction value of serum metabolites in neoadjuvant chemoradiation therapy (NCRT) response for rectal cancer. To date, limited literature is available for serum metabolome changes dynamically through NCRT. Objectives: This study aimed to explore temporal change pattern of serum metabolites during NCRT, and potential metabolic biomarkers to predict the pathological response to NCRT in locally advanced rectal cancer (LARC) patients. Methods: Based on dynamic UHPLC-QTOF-MS untargeted metabolomics design, this study included 106 LARC patients treated with NCRT. Biological samples of the enrolled patients were collected in five consecutive time-points. Untargeted metabolomics was used to profile serum metabolic signatures from LARC patients. Then, we used fuzzy C-means clustering (FCM) to explore temporal change patterns in metabolites cluster and identify monotonously changing metabolites during NCRT. Repeated measure analysis of variance (RM-ANOVA) and multilevel partial least-squares discriminant analysis (ML-PLS-DA) were performed to select metabolic biomarkers. Finally, a panel of dynamic differential metabolites was used to build logistic regression prediction models. Results: Metabolite profiles showed a clearly tendency of separation between different follow-up panels. We identified two clusters of 155 serum metabolites with monotonously changing patterns during NCRT (74 decreased metabolites and 81 increased metabolites). Using RM-ANOVA and ML-PLS-DA, 8 metabolites (L-Norleucine, Betaine, Hypoxanthine, Acetylcholine, 1-Hexadecanoyl-sn-glycero-3-phosphocholine, Glycerophosphocholine, Alpha-ketoisovaleric acid, N-Acetyl-L-alanine) were further identified as dynamic differential biomarkers for predicting NCRT sensitivity. The area under the ROC curve (AUC) of prediction model combined with the baseline measurement was 0.54 (95%CI = 0.43 ~ 0.65). By incorporating the variability indexes of 8 dynamic differential metabolites, the prediction model showed better discrimination performance than baseline measurement, with AUC = 0.67 (95%CI 0.57 ~ 0.77), 0.64 (0.53 ~ 0.75), 0.60 (0.50 ~ 0.71), and 0.56 (0.45 ~ 0.67) for the variability index of difference, linear slope, ratio, and standard deviation, respectively. Conclusion: This study identified eight metabolites as dynamic differential biomarkers to discriminate NCRT-sensitive and resistant patients. The changes of metabolite level during NCRT show better performance in predicting NCRT sensitivity. These findings highlight the clinical significance of metabolites variabilities in metabolomics analysis. [ABSTRACT FROM AUTHOR]

P2X receptors are a class of nonselective cation channels widely distributed in the immune and nervous systems, and their dysfunction is a significant cause of tumors, inflammation, leukemia, and immune diseases. P2X7 is a unique member of the P2X receptor family with many properties that differ from other subtypes in terms of primary sequence, the architecture of N- and C-terminals, and channel function. Here, we suggest that the observed lengthened β2- and β3-sheets and their linker (loop β2,3), encoded by redundant sequences, play an indispensable role in the activation of the P2X7 receptor. We show that deletion of this longer structural element leads to the loss of P2X7 function. Furthermore, by combining mutagenesis, chimera construction, surface expression, and protein stability analysis, we found that the deletion of the longer β2,3-loop affects P2X7 surface expression but, more importantly, that this loop affects channel gating of P2X7. We propose that the longer β2,3-sheets may have a negative regulatory effect on a loop on the head domain and on the structural element formed by E171 and its surrounding regions. Understanding the role of the unique structure of the P2X7 receptor in the gating process will aid in the development of selective drugs targeting this subtype. [ABSTRACT FROM AUTHOR]

Gene therapy has been developed for decades, but is still hampered for general clinical treatment by lack of gene delivery vectors with high transfection efficiency and low cytotoxicity. In this study, well-defined BAB triblock copolymer, poly(glycidyl methacrylate-b-propylene oxide-b-glycidyl methacrylate), P(GMA-b-PO-b-GMA), was prepared via atom transfer radical polymerization and modified by different ratios of ethylenediamine (EDA) and 1-(3-aminopropyl) imidazole (API) to obtain cationic amphiphilic polymers. The difference in the ratio of EDA and API had an influence on pDNA-binding capability, size, and zeta potential of P(GMA-b-PO-b-GMA) derivatives. All the cationic amphiphilic polymers exhibited low cytotoxicity and good transfection activity in comparison with 25 kDa polyethylenimine (PEI) due to their special architecture. The optimal polymer, with 89% API and 11% EDA, showed the highest transfection efficiency among these polymers. Its luciferase expression at N/P ratio of 30 was comparable to that of 25 kDa PEI in a serum-free medium and higher than that of 25 kDa PEI by roughly an order of magnitude in a medium with serum. [ABSTRACT FROM PUBLISHER]

Carbon materials are considered as the ideal electrode materials for supercapacitors due to their diverse structure and nature. However, their poor frequency response is an obstacle to their application in high-frequency supercapacitors. Herein, an ultra-high temperature graphitization process at 2800 °C is proposed to fabricate carbon nanotubes/graphene hybrid films that are successfully employed as the electrode materials of high-frequency supercapacitors. By rational hybridization, the carbon nanotubes/graphene interlinked networks offer fast ion transport paths. Importantly, via a graphitization process at 2800 °C, the as-obtained hybrid films exhibit an ultrahigh in-plane conductivity of 491.81 S cm−1 and favorable out-plane conductivity of 27.98 mS cm−1. Such design brings the as-constructed high-frequency supercapacitors an unprecedented phase angle (up to −56.23°) and area capacitance (up to 230.56 μF cm−2) at 120 Hz, and their cut-off frequency can be nearly 30 times higher than that of films carbonization at 1600 °C. Such increases, further supported by density functional theory (DFT) calculations, are partly attributable to enhancements of ion response arising from the repair of edge defects of graphene. These findings will provide a new method in designing the structure of carbon electrodes for enhancing SCs frequency response performances. Graphitization is proposed to fabricate carbon nanotubes/graphene hybrid films that are employed as electrode materials for high-frequency supercapacitors. The as-obtained hybrid films exhibit excellent electron and ion transport properties due to high conductivity and few exposed graphene edges. These resulting supercapacitors exhibit excellent rate capability. [Display omitted] [ABSTRACT FROM AUTHOR]

Highly conserved amino acids are generally anticipated to have similar functions across a protein superfamily, including that of the P2X ion channels, which are gated by extracellular ATP. However, whether and how these functions are conserved becomes less clear when neighboring amino acids are not conserved. Here, we investigate one such case, focused on the highly conserved residue from P2X4, E118 (rat P2X4 numbering, rP2X4), a P2X subtype associated with human neuropathic pain. When we compared the crystal structures of P2X4 with those of other P2X subtypes, including P2X3, P2X7, and AmP2X, we observed a slightly altered side-chain orientation of E118. We used protein chimeras, double-mutant cycle analysis, and molecular modeling to reveal that E118 forms specific contacts with amino acids in the "beak" region, which facilitates ATP binding to rP2X4. These contacts are not present in other subtypes because of sequence variance in the beak region, resulting in decoupling of this conserved residue from ATP recognition and/or channel gating of P2X receptors. Our study provides an example of a conserved residue with a specific role in functional proteins enabled by adjacent nonconserved residues. The unique role established by the E118-beak region contact provides a blueprint for the development of subtype-specific inhibitors of P2X4. [ABSTRACT FROM AUTHOR]

Although the extracellular ATP-gated cation channel purinergic receptor P2X5 is widely expressed in heart, skeletal muscle, and immune and nervous systems in mammals, little is known about its functions and channel-gating activities. This lack of knowledge is due to P2X5's weak ATP responses in several mammalian species, such as humans, rats, and mice. WT human P2X5 (hP2X5Δ328-349) does not respond to ATP, whereas a full-length variant, hP2X5 (hP2X5-FL), containing exon 10 encoding the second hP2X5 transmembrane domain (TM2), does. However, although rat P2X5 (rP2X5) has a fulllength TM2, ATP induces only weak currents in rP2X5, which prompted us to investigate the mechanism underlying this small ATP response. Here, we show that single replacements of specific rP2X5 residues with the corresponding residues in hP2X5 (S191F or F195H) significantly enhance the current amplitude of rP2X5. Using a combination of engineered disulfide crosslinking, single-channel recording, and molecular modeling, we interrogated the effects of S191F and F195H substitutions on the allostery of the left flipper (LF) domain. On the basis of our findings, we propose that the bound ATP-induced distinct allostery of the LF domain with that of other functional subtypes has caused the weak ATP response of rP2X5 receptors. The findings of our study provide the prerequisite for future transgenic studies on the physiological and pathological functions of P2X5 receptors. [ABSTRACT FROM AUTHOR]

Traffic speed meters are important legal measuring instruments specially used for traffic speed enforcement and must be tested and verified in the field every year using a vehicular mobile standard speed-measuring instrument to ensure speed-measuring performances. The non-contact optical speed sensor and the GPS speed sensor are the two most common types of standard speed-measuring instruments. The non-contact optical speed sensor requires extremely high installation accuracy, and its speed-measuring error is nonlinear and uncorrectable. The speed-measuring accuracy of the GPS speed sensor is rapidly reduced if the amount of received satellites is insufficient enough, which often occurs in urban high-rise regions, tunnels, and mountainous regions. In this paper, a new standard speed-measuring instrument using a dual-antenna Doppler radar sensor is proposed based on a tradeoff between the installation accuracy requirement and the usage region limitation, which has no specified requirements for its mounting distance and no limitation on usage regions and can automatically compensate for the effect of an inclined installation angle on its speed-measuring accuracy. Theoretical model analysis, simulated speed measurement results, and field experimental results compared with a GPS speed sensor with high accuracy showed that the dual-antenna Doppler radar sensor is effective and reliable as a new standard speed-measuring instrument. [ABSTRACT FROM AUTHOR]

The expression and functions of microRNA (miR)-320 have been previously investigated in various types of cancer. However, to the best of our knowledge, no previous studies have investigated miR-320 in human lung cancer. The current study determined the expression, biological functions and molecular mechanisms of miR-320 in human lung cancer. The expression level of miR-320 in human non-small cell lung cancer (NSCLC) and normal adjacent tissue samples (NATs), NSCLC cell lines and non-tumorigenic bronchial epithelial cells was measured by reverse transcription-quantitative polymerase chain reaction. Following transfection with miR-320 mimics, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, cell migration and cell invasion assays, western blot analysis and luciferase assay were performed in human NSCLC cell lines. The results demonstrated that miR-320 was significantly downregulated in NSCLC tissue samples and cell lines compared with NATs and a control cell line, respectively. Statistical analysis demonstrated that expression of miR-320 was significantly associated with the TNM classification and metastasis. It was also observed that miR-320 inhibited cell growth, migration and invasion in NSCLC cells. Additionally, the present study provided evidence that miR-320 may directly target fatty acid synthase. These results suggest that miR-320 may serve as a therapeutic biomarker of NSCLC in the future. [ABSTRACT FROM AUTHOR]

Significant progress has been made in understanding the roles of crucial residues/motifs in the channel function of P2X receptors during the pre-structure era. The recent structural determination of P2X receptors allows us to reevaluate the role of those residues/motifs. Residues Arg-309 and Asp-85 (rat P2X4 numbering) are highly conserved throughout the P2X family and were involved in loss-of-function polymorphism in human P2X receptors. Previous studies proposed that they participated in direct ATP binding. However, the crystal structure of P2X demonstrated that those two residues form an intersubunit salt bridge located far away from the ATP-binding site. Therefore, it is necessary to reevaluate the role of this salt bridge in P2X receptors. Here, we suggest the crucial role of this structural element both in protein stability and in channel gating rather than direct ATP interaction and channel assembly. Combining mutagenesis, charge swap, and disulfide cross-linking, we revealed the stringent requirement of this salt bridge in normal P2X4 channel function. This salt bridge may contribute to stabilizing the bending conformation of the β2,3-sheet that is structurally coupled with this salt bridge and the α2-helix. Strongly kinked β2,3 is essential for domain-domain interactions between head domain, dorsal fin domain, right flipper domain, and loop β7,8 in P2X4 receptors. Disulfide cross-linking with directions opposing or along the bending angle of the β2,3-sheet toward theα2-helix led to loss-of-function and gainof- function of P2X4 receptors, respectively. Further insertion of amino acids with bulky side chains into the linker between the β2,3-sheet or the conformational change of the α2-helix, interfering with the kinked conformation ofβ2,3, led to loss-of-function of P2X4 receptors. All these findings provided new insights in understanding the contribution of the salt bridge between Asp-85 and Arg-309 and its structurally coupled β2,3-sheet to the function of P2X receptors. [ABSTRACT FROM AUTHOR]

FMRFamide (Phe-Met-Arg-Phe-NH2) -activated sodium channel (FaNaC) is an amiloride sensitive sodium channel activated by endogenous tetrapeptide in invertebrates, and belongs to the epithelial sodium channel/degenerin (ENaC/DEG) superfamily. The ENaC/DEG superfamily differs markedly in its means of activation, such as spontaneously opening or gating by mechanical stimuli or tissue acidosis. Recently, it has been observed that a number of ENaC/DEG channels can be activated by small molecules or peptides, indicating that the ligand-gating may be an important feature of this superfamily. The peptide ligand control of the channel gating might be an ancient ligand-gating feature in this superfamily. Therefore, studying the peptide-recognition of FaNaC channels would advance our understanding of the ligand-gating properties of this superfamily of ion channels. Here we demonstrate that Y131, N134, D154 and I160, located in the putative upper finger domain of helix aspersa FaNaC (HaFaNaC) channels, are key residues for peptide recognition of this ion channel. Two HaFaNaC-specific insertion motifs among the ENaC/DEG superfamily, residing at the putative α4-α5 linker of the upper thumb domain and the α6-α7 linker of the upper knuckle domain, are also essential for the peptide recognition of HaFaNaC channels. Chemical modifications and double mutant cycle analysis further indicated that those two specific inserts and key residues in the upper finger domain together participate in peptide recognition of HaFaNaC channels. This ligand recognition site is distinct from that of acid-sensing ion channels (ASICs) by a longer distance between the recognition site and the channel gate, carrying useful information about the ligand gating and the evolution of the trimeric ENaC/DEG superfamily of ion channels. [ABSTRACT FROM AUTHOR]

Subacute combined degeneration of the spinal cord (SCD) is often found in vitamin B-12 deficiency and typically shows hyperintensity on T2-weighted images of the lateral and posterior columns. The purpose of the study was to evaluate the use of conventional magnetic resonance examination in diagnosing SCD. Thirty-six patients were clinically confirmed and retrospectively analyzed; conventional spine MRIs were available for all patients and eight of them had contrast enhancement MRIs. 19 out of 36 patients showed abnormal signal intensity on T2 weighted images with a sensitivity of 52.8%, among which 18 in the posterior aspect of the spinal cord and 1 in the anterior horn of the thoracic spinal cord The spinal cord abnormalities were seen at the cervical spine in 12 patients (33.3%) and at the thoracic spine in the other 7 patients (19.4%). Axial T2-weighted images showed symmetric linear T2-hyperintensity as an "inverted V" at the cervical spinal cord in 5 patients, which has been reported as a typical sign of SCD. For patients with thoracic spinal cord abnormalities, the bilateral paired nodular T2-hyperintensity looked like "binoculars" at the thoracic spinal cord. Only one out of the eight patients showed slight enhancement after injection with contrast agent. All the 36 patients reported clinical improvement after appropriate vitamin B-12 treatment. The two follow-up spine MRIs showed a decreased extent of the lesion. Therefore, conventional MRI is useful in the diagnosis and management of SCD caused by vitamin B-12 deficiency. [ABSTRACT FROM AUTHOR]

Background: A mammary-type myofibroblastoma is a rare soft tumor; extramammary myofibroblastomas are especially rare. Case presentation: A 51-year-old woman presented to our department for evaluation of a mass on the right lower abdominal wall. The mass was then excised completely. Gross examination showed a huge, well-circumscribed soft tissue mass. The pathologic diagnosis was an extramammary myofibroblastoma. There was no recurrence after excision at the 6-month follow-up visit. Conclusions: A mammary-type myofibroblastoma is a benign soft tissue neoplasm. No malignant behavior and/or recurrence of mammary-type myofibroblastomas after surgical resection have been described as a function of size and location. The present case aimed to provide a possible differential diagnosis for such abdominal masses. [ABSTRACT FROM AUTHOR]

The heat shock protein 20 (HSP20) gene of Babesia orientalis (BoHSP20) was identified from both genomic DNA and cDNA. The full-length BoHSP20 gene was 690 bp with one intron from position 88-243 bp. The amplicon obtained from cDNA corresponded to a full-length open reading frame (ORF) with a length of 534 bp, encoding a polypeptide of 178 amino acid residues with a predicted size of 20 kDa. The ORF was cloned into a pET-28a plasmid and subsequently expressed as a His-fusion protein. The recombinant HSP20 of B. orientalis (rBoHSP20) was purified and evaluated as an antigen using Western blotting. Anti-B. orientalis water buffalo serum reacted with rBoHSP20, indicating that this protein was an immunodominant antigen and could be a useful diagnostic reagent to detect antibodies against B. orientalis in water buffalo. The native BoHSP20 was recognized by polyclonal antibody from the serum of rabbit immunized with rBoHSP20. Strong immunofluorescence signals were observed from B. orientalis in blood smears by fluorescence microscopy. Bacterial survival experiments indicated that HSP20 can significantly increase the viability of bacteria when the culture is exposed to thermal stress. The results suggest that BoHSP20 might play an important role during B. orientalis transmission from tick to host animal, given the sudden shifts in temperature involved. Phylogenetic analysis revealed that B. orientalis is in the Babesia clade and most closely related to Babesia bovis. Similar topologies were obtained from trees based on 18S rRNA and the HSP70 gene. The present study suggests that BoHSP20 might be a potential diagnostic antigen and that the HSP20 genes can aid in the classification of Babesia and Theileria species. [ABSTRACT FROM AUTHOR]

To investigate the use of shortened contrast injection with late triggering in coronary CT angiography (CCTA) for decreasing contrast dose and maintaining image quality. 106 patients for CCTA on a 16-cm wide-detector CT were prospectively enrolled into groups A (n = 50) and B (n = 56) randomly. Patient weight-dependent contrast medium (Iopamiro, 370 mgI ml−1) at dose rate of 25 mgI/kg/s was used with 8 s and the standard 10 s injection time in groups A and B, respectively. CT values of the aortic sinus (AS), right coronary artery, left anterior descending and left circumflex at the proximal, middle and distal segments were measured and compared. Subjective image quality was evaluated and analyzed with Fisher exact test. Contrast dose, injection rate and enhancement duration (between the start of enhancement in AS and scan finish) were also compared. There was no difference in the injection rate and enhancement duration between the two groups (p > 0.05), while the total contrast dose in group A (36.2 ± 5.7 ml) was significantly lower than in group B (46.4 ± 6.3 ml) (p < 0.001). There was no difference for CT values in all major coronary vessels between the two groups and no difference in subjective image quality scores (all p > 0.05). It is feasible to shorten contrast injection to 8 s in CCTA on wide-detector CT systems to significantly reduce contrast dosage, maintain adequate enhancement and reduce contrast-related artifacts. (1) Coronary CT angiography (CCTA) scans with shortened contrast medium injection duration and late triggering are feasible with a 16-cm wide-detector CT system (2) Compared with the conventional CCTA with 10 s contrast injection duration, the new contrast injection protocol of using shortened injection duration (to 8 s) and late triggering reduces contrast dose to 36.2 ml, while maintaining adequate enhancement in vessels and reducing contrast-related artifacts. [ABSTRACT FROM AUTHOR]

Schwannomas are slow-growing mesenchymal neoplasms that arise from Schwann cells with low malignant potential. These uncommon neoplasms are nerve sheath tumors that arise at almost any anatomical site. The majority of schwannomas are benign, and few are malignant. The current study presents the rare case of an anal schwannoma that was successfully treated by surgery; there are few such cases previously reported in the literature. The patient was admitted to hospital following the identification of a mass incidentally. The tumor was so large that it compressed the tissue around it, although no symptoms were caused. The pre-operative clinical diagnosis was inconclusive in this case, and a final diagnosis was established based on radiographic and histopathological examination. The current study aimed to provide a possible differential diagnosis for such anally-located masses. [ABSTRACT FROM AUTHOR]